NuSTAR + XMM Observations of NGC 1365: A Constant Inner Disc Dom Walton Caltech G. Risaliti, F. Harrison, E. Kara, M. Parker, E. Rivers, on behalf of the NuSTAR active galaxy working groups
Black Hole Spin Supernova & gamma-ray bursts (stellar black hole binaries) Relativistic jets (both stellar black hole binaries and active galaxies) Galaxy evolution and supermassive black hole formation (active galaxies)
Measuring Black Hole Spin a* = 0 a* = 1 NASA/CXC/M.Weiss The radius of the innermost stable circular orbit depends on the spin (Bardeen et al. 1972).
Relativistic Disk Reflection νf ν νf ν ν ν
Relativistic Disk Reflection Characterising the disc reflection component is one way in which we can measure black hole spin for both binaries and active galaxies NuSTAR Fabian et al. (2000)
NuSTAR Spin Program NuSTAR is performing observations of both Galactic black hole binaries and active galaxies with the purpose of constraining their spin, including (among others): Active galaxies: Source Coordina-on NGC 1365 XMM (x4) MCG- 6-30- 15 XMM Mrk 335 Suzaku Swi> J2127 XMM NGC 4151 Suzaku 3C 120 XMM Fairall 9 XMM Galactic binaries: Source Coordina-on Cygnus X- 1 Suzaku GRS 1915+105-4U 1630-47 - 4U 1957+11 XMM IC 10 X- 1* Chandra (see also talk by G. Matt tomorrow) *Thermal continuum method to be utilized
Black Hole Spin: Recap
Complex Absorption
NGC 1365 NGC 1365 Risaliti et al. (2013, Nat)
NGC 1365 NGC 1365 Risaliti et al. (2013, Nat)
NGC 1365: NuSTAR+XMM V 0 -tv XMM NuSTAR V t t nv t nv k-v 0 V 0 V 0 -t0 -t. -te V V te d Vk Walton et al. (2014) g Vk 0k gk te d Characteristic signatures of disc reflection present regardless of the level of line-of-sight absorption (see poster Theme Message F28 (List by 3 strengths E. Rivers?) focusing on absorption variability)
NGC 1365: Variability btrvt / btrvt btrvi. btrvi Tyvrb b bn b yv D v r v t i o T m ( ) P vr vv vt vi vo vt vm TyvrsiyTb b t v rot r T vr o vr T r T vr o vr T T vr o vr T r T vr o vr T b bn D Walton et al. (2014) Displays both long and short timescale variability, some intrinsic, some due to variable absorption
NGC 1365: NuSTAR+XMM Extracted spectra from 16 time intervals Modelled data above and below 10 kev separately Below 10 kev: absorbed powerlaw and broad iron emission line Above 10 kev: powerlaw (same as below 10 kev) and a reflected continuum (pexrav) Good correlation between EW of the broad line and R 83 8 73 7 63 Walton et al. (2014) 638 639 63 63 63 63 63 63 5 (
NGC 1365: NuSTAR+XMM ho 1 h 2h 6 ho ho 1hh 1h h ho ho 1 h 2.g ) h χh h h 1 2 3 4 Walton et al. (2014) h h ho2 ho4 hoχ ho 1 The black hole spin and the disc inclination obtained are consistent for all four observations, even allowing for variable, partially covering absorption
NGC 1365: X-ray Reverberation Kara et al. (2014, sub.) Clear reverberation (time delay) from the broad Fe K line, and marginal detection from the Compton hump, implies a compact (R <~ 10 R G ) emission region (Uttley, Kara, Zoghbi talks tomorrow)
Conclusions Our 4 coordinated NuSTAR + XMM observations of NGC 1365 reveal an extreme level of absorption variability, yet show the same characteristic signatures of reflection from the inner accretion disc Broad Fe K line and the Compton hump are correlated, each observation independently returns the same BH spin and disc inclination, and X-ray reverberation now detected These results confirm NGC 1365 hosts a rapidly rotating BH The combination of NuSTAR and XMM allows us to resolve long-standing degeneracies regarding the interpretation of the spectral features observed from AGN
NGC 1365: NuSTAR+XMM (5 (. s. 5 Walton et al. (2014; sub.) Correlation between EW broad and R is not simply due to parameter degeneracies associated with the simple models used